Autoimmunity

Autoimmunity defines a state in which the natural immunologic tolerance or unresponsiveness to self-antigen terminates. As a result, immune responses against the self- antigens induce pathology, known as autoimmune diseases. These are now considered a major medical problem of today’s industrialized societies. With the major advances in veterinary immunology, autoimmune disorders are being identified in animals and birds too. The term autoimmunity was first introduced by Paul Ehrlich to convey immunity against self. Autoimmunization needs all the components and mechanism of the immune system but to cause self-destruction in the host, it requires to overcome all those mechanisms that prevents the harmful effects of the autoimmunity. In autoimmunity, problem does not lie in autoantibodies or T-cells that cause the lesions in the disease but lie in the complex network of components that stimulate the event. The complexity of the problem was further compounded by the fact that autoimmunity is an inherent property of the normal immune system. Therefore, despite the major development in the field of immunology, a unifying concept to explain the origin and pathogenesis of various autoimmune disorders is yet to the established. Experimental evidences are, however, accumulating in favour of the opinion that autoimmune disease may result from a wide variety of genetic, environmental, and immunological factors. Classical examples of systemic autoimmune diseases are systemic lupus erythematosus (SLE), rheumatoid arthritis, canine dermatomyositis, Sjogren’s syndrome, and vasculitides.